Sectional grinding wheel



July 29. 1924. K

F. J. TONE SECTIONAL GRINDING WHEEL Filed Feb. 23, 1922 2 Sheets-Sheet. l

INVENTOR July 29 1924. 1,502,697

F. J. TONE SECTIONAL GRINDING WHEEL Filed Feb. 23 Q 1922 2 Sheets-Sheet 2 .INVENTOR WIWI/ZWB1M Patented July 29, 1924.

STATES PATENT OFFICE.

FRANK J'. TONE, OF NIAGARA FALLS, NEW'YORK, ASSIGNOR TO THE CARBORUNDIJM COMPANY, OF NIAGARA FALLS, NEW YORK, A CORPORATION OF PENNSYLVANIA.

SECTIONAL GRINDING WHEEL.

Application filed February 23, 1922. Serial No. 538,823.

To all whom it may concern:

Be it known that I, FRANK J. TONE, residing at Niagara Falls, in the county of Niagara and State of New York, have invented a new and useful Improvement in Sectional Grinding Wheels, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming part of this specification, in which- Figure l is a side elevation showing one form of grinding wheel constructed in ac cordance with my invention;

Figure 2 is a cross section on the lin IIII of Figure 1;

Figure 3 is a partial section through the removable portion of an intermediate undercut rib;

Figure 4 is a perspective view of one of the abrasive blocks;

Figures 5 to 11, inclusive, are detail views of modified forms;

Figures 12 and 13 are an end elevation ang cross section showing a modified form; an

Figures 14 and 15 are an end elevation and cross section showing another modified form.

My invention relates to sectional grinding wheels, wherein a metal drum holds seg mental sections of abrasive material on its periphery. The invention is designed to provide an improved system of mounting the sections on the drum, which is especially designed for grinding wheels used in the manufacture of wood pulp, although it may be used for other purposes.

These wheels as now used for grinding wood pulp are ordinarily of natural sandstone and yary from inches to 60 inches in diameter when first installed and from 20 inches to 50 inches in width. After the wheel has been worn down so that the diameter is reduced by 16 or 20 inches, the wheel is removed and scrapped.

When it is proposed to increase output, decrease power consumption and obtain other advantages of substituting the artificial abrasive for the natural sandstone, the question of expense of the wheels becomes very important and the loss in discarding grinding material not used is important,

It is difficult to mold and manufacture solid walls of artificial abrasive of the size required in pulp grinding, and hence, the segential flanges for gripping and holding the abrasive segments. .In the form shown, this drum has two other flanges or ribs 3 and 4, and two inner or intermediate flanges or ribs 5 and 6, all of which throughout their major portions are preferably cast or otherwise made integral with the drum. The operative side faces of these flanges are preferably undercut, as shown. The abrasive blocks 7 may be molded from silicon carbide, aluminous abrasive or any other suitable abrasive, the grains of which are bonded together with a vitrified binder, or any other type of bonding material desirable therefor.

These abrasive blocks are in the form of segments and are molded with curved dovetailed recesses 8, 8, extending along the lower edge of both of the sides normal to the drum axis, these recesses engaging the corresponding undercut portions of the flanges. The space between any two flanges forms a channel containing a circular row of segmental blocks. To allow entrance of the molded blocks into these channels, I provide 'a gate entrance, by removing part of a flange or rib, this ate being of a length slightly greater than-t e base length of the block and being detachably fastened inplace after the blocks are inserted.

It is possible to use a single series of segments, each segment being gripped by the outside flanges. However. in wheels of a desirable width for wood pulp grinding, the blocks in such case would be of excessive length when worn down thin-and would not have proper resistance to rupture to withstand the centrifugal force or the pressure for the outer flange 3 is shown in Figures 1 and 2, being held by axial screws passing through an inwardly projectlng flange on vthe drum. The same is the case with a pordrums closely, but space is providedforcement between the blocks and the drum, between the blocks and the flanges and also between the individual blo'cks. The cement may consist of molten sulphur, Portland cement or any other suitable cement. The

blocks maybe cemented one at a time as they are brought to place, or they may be cemented all at one time after the assembling.

The circumferential joints between the segmental blocks of the central row are preferably staggered relative to the joints of the adjacent outer rows.

The gate entrance may be formed in other ways, and I show one modification in Fig ures 5 and 6, Figure 6 being a cross section on. the line VIVI of Figure 5. In this form, a portion of the flange equal in length over the balance of the flange, but set ,awaying, as shown at 12, or cap screws bearing on .with the recesses of thefiange.

' to one block segment is provided with a dovetailed recess parallel with the recess from the segment a suflicient distance to al low the segment to be inserted readily and brought to its seat on the drum. After the segments are inserted in this particular space and shoved around to position, the space between the flange and last segment may be filled up with cement or wedges, or fillers may be inserted from beneath before cementthe segment may be used in conjunction with the cement. l y

A further modification is shown in Figures 7 to 11, inclusive. Figure 7 is a developed view of a portion of the surface of the drum, including one outside flange 3 and an intermediate flange 5", Figure 8 being a section on the line VIII-VIII of Figure 7.

In this form, the block segments are of the shape shown in Figures 10 and 11, the base portion being formed with a short dovetail, then an equal space without a dovetail, and so on, so that the block can be readily inserted in its channel, these projections. merging After insertion, it is then moved circumferentially to place, as before. In this modification,

Figure 9 is a side view of a segment in the direction-of the drum axis.

In Figures 12 and 13 is shown another modified form,-in which the invention is illustrated as applied to a wheel having one circumferential row of abrasive blocks. A gate opening 20- is formed through the drum, so that the blocks 21 may be inserted from the interior of the drum throu h the gate opening. The blocks are pushed into place and slid around into position, being retained by the dovetailed base22 of the blocks cooperating with the undercut flanges 23. After' the blocks are inserted, the gate opening 20 is closed by the plate 24 bolted to the drum. The blocks after being put into place are cemented.

.In Figures 14 and 15, is illustrated another modification in which the blocks are inserted radially from the outside of the mg provided at these places withremovable flanged sections. The blocks are inserted at the cut-away portions and are slid into place until the two opposite rows 01' blocks 31 are filled up. Then the blocks are inserted and the center row 32 is filled. After the rows of blocks are filled, the removable segments are inserted.- Each of these removable segments comprises three parts, namely, undercut oppositely facing ribs 33 and 34;, and a key 35, inserted between them. The outer undercut ribs 33 and 34: are first inserted and fitted into the dovetailed portions of the blocks. Then the key 35 is inserted and the three parts secured together by the bolts 36. The entire assembly of the flan ed segment is then bolted to the drum by 5e bolts 37, extending through wings on the flanged sections 33 and 34. The blosks are then cemented in the usual way.

All these modifications involve a construction which will allow the insertion of the block segment to its line osition and then moving the segment circumferentially to a position between the fixed flange portions where the dovetailed portions are engaged,

the segment then being secured as by cementmg.

Theblocks are cemented in their position on the drum. In the construction shown, when the flan es are cast integrally with or permanently astened to the drum and where the segments loosely fit the recesses or channels so as to allow their being slid around to the proper osition, the cement performs an important otion. When set, it causes equalizing and distributing of the stresses from centrifugal forceand insures a proper fit between the segment and the drum to 've support under the great pressnres to wfiich the segment is subjected on grinding. The

surfaces of these blocks are more or less aongh and this cementing makes it unnecesloo 1.

sary for close fitting and saves considerable expense in fitting.

ile my construction has been described in several forms, particularly applicable for wood pulp grinding, it may, of course, be used for any form of grinding. Furthermore, while I have shown and described undercut or dovetailedarrangements of the flanges and segments, equivalents thereof may be used. For example, I may use a square lug engaging a square recess on the segment block, or may employ lugs or flanges or curved or or othersections to engage corresponding molded recesses in the blocks. Any number of rows of blocks may be used, other means of gating or insertion may be employed, different forms of abrasives and binders may be'used in forming the blocks, and otherchanges may be made without departing from my invention.

I claim: 1". A grinding wheel including, a supporting drum, segmental blocks of grinding material arranged in a plurality of circumferential rows, and means common to adj acent rows and extending circumferentially of the drum for retaining the segments thereon.

2. A grinding Wheel including a supporting drum, segmental blocks of grinding material arranged in a plurality of circumferential rows, the circumferential joints between adjacent rows being staggered, and means common to adjacent rows and extending circumferentially of the drum for retaming the segments thereon. v

3. A grinding wheel including a supporting drum, segmental blocks of grinding material arranged in a plurality of circumferential rows, and dovetail means common to adjacent rows and extending circumferentially of the drum for retaining the seg-,

ments thereon.

4. A grinding wheel including a supporting drum, segmental blocks of grinding material arranged in a plurality of circumferential rows, and dovetail means common to adjacent rows and extending circumferentially of the drum for retaining the segments thereon, the blocks projecting to varying distances from said means.

said means holding the last block inthe wheel after it has been introduced.

6.'A grinding wheel including a supporting drum, segmental blocks of grinding material arranged ,in a plurality of circumferential rows on said drum, retaining flanges at the ends of said drum for engaging the end faces of the blocks at the ends of the Wheel, and an intermediateretaining flange extending circumferentially of the drum and engageable with the blocks of adjacent rows.

7. A grinding wheel including a supporting drum, segmental blocks of grinding material arranged in a plurality of circumferential rows on said drum, retaining flanges at the ends of said drum for engaging the end faces of? the blocks at the ends of the wheel, and an intermediate retaining flange extending circumferentially of the drum and engageable with the blocks of adjacent rows, at least a portion of said intermediate flange the grinding blocks on the drum.

8. A grinding wheel including a supporting drum, segmental .blocks of grinding material arranged in a plurality of circumferential rows on said drum, retaining flanges'at the ends of said drum for engagingthe end faces of the blocks at the ends of the wheel, and an intermediate retaining flange extending circumferentially of the drum and engageable with the blocks of adjacent rows, atleast a portion of each of the retaining flanges at the ends of the drum bein removable to facilitate assembly of the 'being removable to facilitate assembly of grin ing blocks on the drum.

In testimony whereof I have hereunto set my hand.

' FRANK J.'TONE. 

